Multi-die integrated circuits (ICs) are a class of ICs in which multiple dies are placed within a single package. A multi-die IC also can be referred to as a “system in a package” or “SiP.” The multiple dies communicate with one another often at faster speeds than is attainable were the dies to be implemented as two or more individual IC packages mounted on a printed circuit board.
ICs that include a single die can generate a significant amount of heat. As the number of dies included within a single package increases, so too can the heat generated by the resulting structure. As such, a multi-die IC can generate a significant amount of heat and, in some cases, more than is typically generated by single die ICs. Further, the architectural features of a multi-die IC structure can make the regulation of heat dissipation difficult.
Dissipating heat is an important aspect of IC design for a variety of reasons. For example, devices such as transistors that are implemented within ICs tend to operate more slowly with increasing temperature. In another example, increases in the temperature of an IC structure can exacerbate stresses within the IC. Stresses can occur due to the varying expansion rates of the component materials used to fabricate a semiconductor IC.